Ends down detector apparatus

ABSTRACT

An ends down detector apparatus for detecting the absence of any ends in a series of yarns on a textile machine, such as a spinning frame, and wherein the apparatus includes means for generating electrical pulse signals of varying magnitudes, the intact running ends of yarns cooperating with the generating means to effect electrical pulse signals of a predetermined magnitude denoting the presence of ends of yarns and wherein means are positioned in advance of the series of yarns to effect electrical pulse signals of a higher magnitude than effected by the intact ends of yarns for re-setting the electrical circuit and thereby controlling proper cyclic operation thereof as the ends down detector apparatus moves along the series of yarns.

0 United States Patent [151 3,659,407 Saunders 1 1 May 2, 1972 1 1 ENDS DOWN DETECTOR APPARATUS 3,523,413 8/1970 Ford et a1. .57/34 [72] Inventor: my w Saunders, Fitchburg Mass. 3,523,415 8/1970 Susukr ..57/81 [73] Assignee: Plrks-Cramer Company, Fitchburg, Mass. Emmimr-stanley Gilreath Assistant Examiner-Werner H. Schroeder [22] Filed: June 3, 1970 Attorney-Paxton, Bell, Seltzer, Park & Gibson 21 A 1. No.: 43 036 1 PP v 57 ABSTRACT [52] 11.8. CI. ..57/34 R, 57/81 ends f f 1 W! (fleeting E absence of [51} Int CL I I I Dom any ends 111 a senes of yarns on a textile machine, such as a [58] Field of semh' I 57/34 5 78 spinning frame, and wherein the apparatus includes means for 57/81, 19; 250/219; 340/259; 242/355, generating electrical pulse signals of varying magnitudes, the 1 intact running ends of yarns cooperating with the generating [56] Rfluences cued means to effect electrical pulse signals of a predetermined magnitude denoting the presence of ends of yarns and wherein UNITED STATES PATENTS means are positioned in advance of the series of yarns to effect electrical pulse signals of a higher magnitude than effected by 3,043,991 7/ 1962 schnelder et a1. ..57/8l X the intact ends of yams for fawning the electrical circuit and 3,099,829 Nanlenyl'Katz 57/81 x thereby controlling proper cyclic operation thereof as the 3,1 14,233 12/1963 Gun ..57/8l ends down detector apparatus moves along the series f yams 3,287,887 11/1966 Dornberger ...57/19 3,498,039 3/1970 Kent et a1. ..57/34 9 Claims, 2 Drawing Figures O 0 FE L; 2

PATENIEMAY 21972 3.659467 PHOTO v v I INVENTOR J MULT' PL'EQ bAvlb W. SAU NBERS Tu BE 2.: y- 2 fiiwaimig m 42mm ATTORNEYS ENDS DOWN DETECTOR APPARATUS It has heretofore been proposed that the efficiency of certain textile strand processing operations by improved by providing apparatus for detecting and reporting the ends down condition of textile yarn or thread forming apparatus such as spinning and twisting machines. In accordance with certain of such proposals, apparatus is provided within a textile mill room, such as spinning room, for moving detector means along textile apparatus such as spinning frames.

It is an object of the present invention to control proper cyclic operation of a traveling ends down detector apparatus as the same moves along a series of ends of yarn on a textile machine by incorporating electrical circuit means therein which is responsive to electrical pulse signals of varying magnitudes.

It is a more specific object of this invention to provide an ends down detector apparatus of the type described and wherein means is positioned in advance of a series of ends of yarn for effecting generation of an electrical pulse signal of a higher magnitude than that generated by the intact running ends of yarn for resetting the ends down detector apparatus for proper operation in advance of its movement along the series of ends of yarn.

in accomplishing these objects of the present invention, mechanically actuated elements or mechanically moving elements are avoided in an environment where the reliability of such actuation or movement may be impaired by lint or the like produced by the textile processes. More particularly, the circuit means provided responds to at least two different levels of magnitude of electrical pulse signals originating from a photosensitive detector means for determining the presence and absence of ends of yarn and for resetting an element of the circuit which makes such determination. Stationary means positioned in advance of the series of ends of yarn being formed on the textile apparatus reflects a level of light distinct from that reflected from ends of yarn normally present on the textile apparatus and thereby effects generation of a signal of greater magnitude, to accomplish resetting of the circuit means.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, in which FIG. 1 is an elevation view, partly broken away, of a textile strand forming machine and apparatus for locating ends down thereon in accordance with the present invention; and

FlG..2 is a schematic wiring diagram of electrical circuit means in accordance with this invention.

Referring now more particularly to the drawing, the present invention is particularly concerned with apparatus in which the travel of detector means along textile strand processing apparatus such as spinning frames for locating ends down conditions thereon results from the combination of electrical circuit means with a traveling pneumatic cleaner as generally indicated at in FIG. 1. The traveling pneumatic cleaner 10 is mounted on a track generally indicated at 11 for movement above and along at least one textile strand processing apparatus such as a spinning frame generally indicated at 12. For a more extensive disclosure of the advantages and benefits which flow from such combination, attention is directed to H5. Pat. No. 3,523,413 issue from co-pending application Ser. No. 794,880, filed Jan. 29, 1969, entitled Apparatus and Method For Detecting and Reporting Ends Down on Textile Machines"and owned in common with this application. As the broad relationship of the traveling pneumatic cleaner of FIG. 1 to a textile strand processing apparatus may be more fully understood from the disclosure in the aforementioned copending application and as reference is therein made to other and further pertinent patent disclosures, the present application shall not repeat at length such disclosure, but shall be directed more toward particular electrical circuit means for establishing a lengthwise portion of a traversed textile machine in which an ends down condition is determined by controlling cyclic operation of a resettable element and which is operative in an environment such as that set forth in the aforementioned co-pending application.

Apparatus of the type for which the present invention is an improvement conventionally comprises detector means such as a photosensitive means orother energy level sensing device which is moved along a portion of at least one textile strand processing apparatus in which a series of ends of yarn normally are present or being formed during operation of the apparatus. Further, the apparatus has logic circuit means for determining from the response of the detector means the presence or absence of ends of yarn from locations at which such ends nonnally are present. Typically, the logic circuit means includes an element generating pulse electrical signals upon determination of the absence of ends of yarn, with the pulse electrical signals being passed to a counter. While such specific details are of significance with regard to the present subject invention, this invention contemplates that the detector means and circuit means connected thereto may take forms such as are disclosed in the prior art, including pending applications owned in common with this application, and it is noted that electrical circuit means including detector means and logic circuit means are the subject of patent protection separate from the present invention.

In accordance with the present invention, control over cyclic operation of the logic circuit means or the establishment of a lengthwise portion of the traversed textile machine in which the ends down condition is determined is accomplished by distinguishing between two levels of response of a photosensitive means incorporated in a detector means, thereby avoiding direct physical engagement or mechanical actuation for serving this function. As a result, the present invention both minimizes the possibilities of mechanical malfunction and opens the possibility of more readily adapting pre-existing textile strand processing apparatus to an apparatus of the general type discussed above.

Referring now to FIG. 2, the present subject invention includes electrical circuit means as there schematically illustrated. A first circuit means, enclosed by a dashed line and indicated generally at 20, is electrically connected to a photosensitive means such as a photomultiplier tube indicated generally at 21 and is responsive to pulse signals of a first predetermined magnitude for distinguishing between the absence and presence of ends of yarn at locations along a traversed textile apparatus and in accordance with an operation described more fully hereinafter. A second circuit means enclosed within a dashed line and generally identified by the reference character 30 is also electrically connected to the photosensitive means and operates in a particular manner described more fully hereinafter to apply electrical pulse signals to the first circuit means 20.

Each of the first and second circuit means 20, 30 is coupled to the photosensitive means 21 through a corresponding coupling capacitor C1 and C2 and includes a corresponding set point determining potentiometer P1 and P2. By the inclusion of the coupling capacitors C1, C2, the first and second circuit means 20, 30 are rendered responsive to the rate of change of light incident on the photosensitive means 21 from within a predetermined field of view thereof which is moved along the spinning frame 12 and relative to the series of yarns thereon. That is, electrical signals from the photosensitive means 21 which are indicative of only a slow change in the level of illumination directed thereto, and which usually are present as variations in a direct current voltage level, are not applied through the coupling capacitors Cl and C2 to the first and second circuit means 20, 30. Upon movement of the detector means including the photosensitive means 21 and a light source illuminating the field of view thereof past a location at which an end of yarn present on the spinning frame 12 is passed through the field of view of the photosensitive means or some other means directs or reflects light thereto, a rapid fluctuation in the level of illumination applied to the photosensitive means 21 generates a pulse signal capable of passing through the coupling capacitors C1 and C2. A pulse signal passing through the corresponding coupling capacitor is amplified by amplifiers 25 and 35 in the respective first and second circuit means, where the amplitude of the incoming signal is sufficient to overcome a saturating input normally applied through the potentiometers P1 and P2, as is known in the application of operational amplifiers.

It is a characteristic of a photosensitive means of the type employed in the detector means, in accordance with the present invention, that the magnitude of the pulse signal generated thereby is dependent upon the level of light directed to the photosensitive means 21. That is, a high level of light directed to the photosensitive means 21 produces a pulse signal of greater magnitude. This characteristic is used to advantage in the arrangement of the present invention, by the provision of a coupling resistor R1 through which a pulse signal must be passed to reach the second circuit means 30. in particular, the disposition of the coupling resistor R1 between the coupling capacitor C2 and photosensitive means 21, in the absence of a similar resistance being inserted between the coupling capacitor C1 and the photosensitive means 21, results in pulse signals of lower magnitude than a predetermined threshold level being blocked from passage to the second circuit means 30 of the present invention. Thus, until such time as a pulse signal generated by the photosensitive means 21 exceeds at least a predetermined magnitude, such pulse signals are applied to the first circuit means 20 but not to the second circuit means 30.

in accordance with the present invention, the resistance value of the coupling resistor R1 is so chosen that a pulse signal originated by a photosensitive means 21 during movement of the field of view thereof across a location at which an end of yarn is present has such a magnitude that the signal is passed to the first circuit means 20 and is blocked from the second circuit means 30. Thus, during traversal of the detector means of the apparatus past a series of yarns and along a lengthwise portion of a traversed textile apparatus in which an ends down condition is to be determined, pulse signals originating from the photosensitive means 21 are applied only to the first circuit means 20.

The first circuit means 20 incorporates a resettable element, preferably in the form of a resettable oscillator functioning as a logic circuit means and comprising a unijunction transistor 22, a timing capacitor C3, a triggering transistor 23 and a timing resistor R2. By adjustment of the resistance value presented by the resistor R2, the time within which the voltage present across the capacitor C3 rises to a predetermined level can be established. On the voltage across the capacitor C3 reaching a predetermined level, the unijunction timing transistor 22 becomes conductive and an output pulse isgenerated by the logic circuit means.

Generation of an output pulse from the unijunction transistor 22 is avoided where the voltage built up on the timing capacitor C3 is discharged to ground at predetermined intervals of shorter duration than the time established by the values of the timing capacitor C3 and timing resistor R2. Such discharge of voltage across the timing capacitor C3 to ground is accomplished on the triggering transistor 23 becoming conductive. Such a change in the conductive state of the triggering transistor 23 occurs in response to a pulse signal originating in the photosensitive means 21, passing through the coupling capacitor C1 into the first circuit means 20, and being amplified and shaped by an amplifier 25 and shaping transistor 26. The operation of the logic circuit means just described relies upon the traveling cleaner moving along and above the spinning frame 12 at a known linear speed and further upon the spacing of the series of yarns along the spinning frame 12 being known. During normal movement of the photosensitive means 21 adjacent a portion of the spinning frame 12 at which ends of yarn are present, periodic pulsing of the triggering transistor 23 at intervals established by movement of the field of view of the photosensitive means 21 across the series of ends of yarn precludes such voltage build up across the timing capacitor C3 as to result in firing of the unijunction timing transistor 22. Otherwise, the resettable oscillator will normally generate output pulse electrical signals at a time interval slightly greater than the interval at which the field of view of the photosensitive means normally traverses locations at which ends of yarn are normally present. in the absence of an end of yarn, the timing capacitor C3 is not discharged to ground and the unijunction timing transistor is fired to distinguish the absence of an end of yarn from a location at which such an end normally is present.

From the above discussion of the operation of the first circuit means 20, it is to be understood that timing of the intervals established by the timing capacitor C3 and timing resistor R2 must begin in pre-determined relation to a lengthwise portion of a traversed textile machine in which an ends down condition is to be determined by the first circuit means 20. As herein used, the terms proper cyclic operation, reset and unreset" relate to such establishment and initiation of the timing cycle, in relation to the lengthwise portion of a spinning frame in which ends down are to be determined. Resetting of the resettable element of the first circuit means 20 is accomplished and proper cyclic operation is controlled by grounding both sides of the timing capacitor C3, independently of any change in conductive state of the triggering transistor 23.

More particularly, the second circuit means 30 is electrically connected to both the photosensitive means 21 as described above and to the resettable element of the first circuit means 20, through a conductor 31 extending between portions of the first circuit means 20 and a control transistor 32 of the second circuit means 30. Upon the photosensitive means 21 generating an output pulse which exceeds the predetermined magnitude established by the blocking resistor R1, the control transistor 32 is rendered conductive and timing capacitor C3 of the first circuit means 20 is grounded through the control transistor 32, a conductor 31 and a diode 37. Such grounding discharges any voltage charge built up on the timing capacitor C3 and initiates the timing cycle which enables the logic circuit means; to distinguish between the presence and absence of ends of yarn at locations along the traversed textile apparatus.

In order to cooperate with the photosensitive means 21 and with the first and second circuit means 20, 30 in the operation described immediately above, the present invention further contemplates the provision of means stationarily positioned relative to a traversed textile apparatus and to the path traveled by the field of view of the photosensitive means 21 for directly to the photosensitive means levels of light higher than the level of light reflected from an end of yarn and thereby establishing a lengthwise portion of the traversed textile apparatus in which an ends down condition is determined by the first circuit means. As illustrated in H0. 1, the means stationarily positioned relative to the traversed textile apparatus preferably comprises at least one highly reflective member mounted on the spinning frame 12 in advance of the first of the series of ends of yarn normally present. As illustrated, the highly reflective member preferably is a polished rod 40, spaced from the closest adjacent spindle location of the spinning frame 12 by a distance generally the same as the gauge of the spinning frame. Thatis, the distance between the highly reflective rod 40 and the next adjacent end of yarn is substantially the same as the distance between adjacent pairs of ends of yarn. In order to accommodate the traveling cleaner 10 in either direction relative to the traversed spinning frame, reflective rods 40 are provided at both ends of the spinning frame 12.

In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation:

What is claimed is:

1. In an ends down detector, which travels along a textile strand processing apparatus such as a spinning frame having a series of ends of yarn being formed thereon for detecting the absence of any ends of yarn, the ends down detector including an electrical circuit having an element resettable from a prior cyclic state for initiating proper cyclic operation thereof and adapted to be reset immediately before the ends down detector begins traveling along a series of ends of yarn; the improvement therewith of the ends down detector including means for generating electrical pulse signals of varying magnitudes, the intact running ends of yarn cooperating with said generating means to effect electrical pulse signals of a predetermined magnitude denoting the presence of ends or yarns, and means positioned in advance of the series of yarns and also cooperating with said generating means to effect electrical pulse signals of a higher magnitude than effected by the intact ends of yarn, said generating means cooperating with said resettable element for effecting resetting thereof in response to said electrical pulse signals of higher magnitude.

2. Apparatus according to claim 1 wherein said ends down detector further includes photosensitive means having a predetermined field of view and being mounted for movement of said field of view along the series of yarns and a light source mounted for illuminating said photosensitive means field of view and for movement therewith along a traversed textile apparatus, said photosensitive means being responsive to reflection of light emanating from said light source.

3. Apparatus according to claim 2 wherein said means positioned in advance of the series of yarns comprises at least one highly reflective member mounted on said traversed textile apparatus in predetermined relation to the location of the first of the series of yarns.

4. Apparatus according to claim 3 wherein said highly reflective member comprises a polished rod.

5. In an apparatus which travels along textile strand processing apparatus such as spinning frames for detecting the absence of any ends of yarn, the improvement therewith of means for controlling proper cyclic operation thereof comprising:

detector means being mounted for movement along a portion of at least one textile apparatus where ends of yarn normally are present, said detector means being responsive to radiant energy directed thereto from bodies such as a series of ends of yarn and the like during movement thereof across positions at which such bodies are disposed for generating electrical pulse signals of varying magnitudes corresponding to the levels of radiant energy received,

first circuit means comprising a resettable element and electrically connected to said detector means for responding to pulse signals of a first predetermined magnitude indicative of the level of energy received from an end of yarn, for distinguishing between the absence and presence of ends of yarn at locations along a textile apparatus traversed while said resettable element remains unreset and at which ends of yarn normally are present, and for registering an ends down condition thus sensed and determined,

second circuit means electrically connected to said detector means for responding to pulse signals of a magnitude greater than said first predetermined magnitude and indicative of a higher lever of energy, said second circuit means being electrically connected to said resettable element of said first circuit means for resetting said resettable element from a prior cyclic state and for initiating proper cyclic operation thereof in response to said greater magnitude pulse signals, and

means positioned along the path traveled by said detector means and in advance of the series of yarns for directing to said detector means levels of energy higher than the level of energy received from an end of yarn and thereby for controlling cyclic operation of said first circuit means.

6. Apparatus according to claim 5 wherein said first circuit means comprises a pulse shaping means electrically connected to said detector means for receiving pulse signals therefrom and for shaping the characteristics of received pulse signals and logic meanselectrically connected to said pulse shaping means for receiving shaped pulse signals therefrom an responsive to normal traversal of said detector means for distinguishing between absence and presence of ends of yarn on a traversed textile apparatus and for generating an output pulse electrical signal upon an end of yarn being absent from a location at which the same normally is present.

7. Apparatus according to claim 6 wherein said pulse shaping means comprises an amplifier for shaping pulse signals originating from said detector means with varying pulse characteristics to a substantially uniform shaped pulse characteristic and said logic means comprises a resettable, freerunning oscillator functioning as said resettable element and normally generating output pulse electrical signals at a predetermined time interval coordinated to normal traversal of said detector means and responsive to receipt of a shaped pulse signal from said pulse shaping circuit means for initiating timing of said predetermined interval, said predetermined time interval being slightly greater than the interval at which said detector means normally traverses locations at which ends of yarn are normally present, so that cadenced resetting of said oscillator by a shaped pulse signal indicative of an end of yarn being present at a traversed location inhibits generating of an output pulse signal by said oscillator.

8. Apparatus according to claim 5 further comprising pulse blocking means for inhibiting passage of pulse signals of said first predetermined magnitude to said second circuit means and wherein said second circuit means comprises shaping means for shaping the characteristics of pulse signals of said greater magnitude.

9. Apparatus according to claim 8 wherein said second circuit means comprises an amplifier for shaping pulse signals originating from said detector means with varying pulse characteristics to a substantially uniform shaped pulse characteristic. 

1. In an ends down detector, which travels along a textile strand processing apparatus such as a spinning frame having a series of ends of yarn being formed thereon for detecting the absence of any ends of yarn, the ends down detector including an electrical circuit having an element resettable from a prior cyclic state for initiating proper cyclic operation thereof and adapted to be reset immediately before the ends down detector begins traveling along a series of ends of yarn; the improvement therewith of the ends down detector including means for generating electrical pulse signals of varying magnitudes, the intact running ends of yarn cooperating with said generating means to effect electrical pulse signals of a predetermined magnitude denoting the presence of ends or yarns, and means positioned in advance of the series of yarns and also cooperating with said generating means to effect electrical pulse signals of a higher magnitude than effected by the intact ends of yarn, said generating means cooperating with said resettable element for effecting resetting thereof in response to said electrical pulse signals of higher magnitude.
 2. Apparatus according to claim 1 wherein said ends down detector further includes photosensitive means having a predetermined field of view and being mounted for movement of said field of view along the series of yarns and a light source mounted for illuminating said photosensitive means field of view and for movement therewith along a traversed textile apparatus, said photosensitive means being responsive to reflection of light emanating from said light source.
 3. ApparaTus according to claim 2 wherein said means positioned in advance of the series of yarns comprises at least one highly reflective member mounted on said traversed textile apparatus in predetermined relation to the location of the first of the series of yarns.
 4. Apparatus according to claim 3 wherein said highly reflective member comprises a polished rod.
 5. In an apparatus which travels along textile strand processing apparatus such as spinning frames for detecting the absence of any ends of yarn, the improvement therewith of means for controlling proper cyclic operation thereof comprising: detector means being mounted for movement along a portion of at least one textile apparatus where ends of yarn normally are present, said detector means being responsive to radiant energy directed thereto from bodies such as a series of ends of yarn and the like during movement thereof across positions at which such bodies are disposed for generating electrical pulse signals of varying magnitudes corresponding to the levels of radiant energy received, first circuit means comprising a resettable element and electrically connected to said detector means for responding to pulse signals of a first predetermined magnitude indicative of the level of energy received from an end of yarn, for distinguishing between the absence and presence of ends of yarn at locations along a textile apparatus traversed while said resettable element remains unreset and at which ends of yarn normally are present, and for registering an ends down condition thus sensed and determined, second circuit means electrically connected to said detector means for responding to pulse signals of a magnitude greater than said first predetermined magnitude and indicative of a higher lever of energy, said second circuit means being electrically connected to said resettable element of said first circuit means for resetting said resettable element from a prior cyclic state and for initiating proper cyclic operation thereof in response to said greater magnitude pulse signals, and means positioned along the path traveled by said detector means and in advance of the series of yarns for directing to said detector means levels of energy higher than the level of energy received from an end of yarn and thereby for controlling cyclic operation of said first circuit means.
 6. Apparatus according to claim 5 wherein said first circuit means comprises a pulse shaping means electrically connected to said detector means for receiving pulse signals therefrom and for shaping the characteristics of received pulse signals and logic means electrically connected to said pulse shaping means for receiving shaped pulse signals therefrom and responsive to normal traversal of said detector means for distinguishing between absence and presence of ends of yarn on a traversed textile apparatus and for generating an output pulse electrical signal upon an end of yarn being absent from a location at which the same normally is present.
 7. Apparatus according to claim 6 wherein said pulse shaping means comprises an amplifier for shaping pulse signals originating from said detector means with varying pulse characteristics to a substantially uniform shaped pulse characteristic and said logic means comprises a resettable, free-running oscillator functioning as said resettable element and normally generating output pulse electrical signals at a predetermined time interval coordinated to normal traversal of said detector means and responsive to receipt of a shaped pulse signal from said pulse shaping circuit means for initiating timing of said predetermined interval, said predetermined time interval being slightly greater than the interval at which said detector means normally traverses locations at which ends of yarn are normally present, so that cadenced resetting of said oscillator by a shaped pulse signal indicative of an end of yarn being present at a traversed location inhibits generating of an output pulse signal by said oscillatoR.
 8. Apparatus according to claim 5 further comprising pulse blocking means for inhibiting passage of pulse signals of said first predetermined magnitude to said second circuit means and wherein said second circuit means comprises shaping means for shaping the characteristics of pulse signals of said greater magnitude.
 9. Apparatus according to claim 8 wherein said second circuit means comprises an amplifier for shaping pulse signals originating from said detector means with varying pulse characteristics to a substantially uniform shaped pulse characteristic. 